JP6956369B2 - Molding materials for light reflectors, light reflectors and light emitting devices - Google Patents

Description

The present invention relates to a molding material for a light reflector suitable for producing a light reflector (reflector), a light reflector manufactured from the molding material for the light reflector, and a light emitting device including the light reflector. ..

Conventionally, it is known to use a light reflector (reflector) to reflect light emitted by a light emitting element such as a light emitting diode. An unsaturated polyester resin is known as one of the resins used for producing a light reflector. The unsaturated polyester resin is composed of an unsaturated polyester and a cross-linking agent such as styrene. Since the unsaturated polyester resin is a thermosetting resin, when it is used, there is an advantage that the heat-resistant discoloration property of the light reflector is increased.

For example, Patent Document 1 describes molding an unsaturated polyester resin composition containing an unsaturated polyester, a copolymerizable monomer or a multimer, and a thermoplastic resin, and an unsaturated polyester resin composition containing a white pigment. It is disclosed that an LED reflector is obtained in the above. Further, Patent Document 1 lists melt heating molding methods such as an injection molding method, an injection compression molding method, and a transfer molding method as molding methods.

Japanese Unexamined Patent Publication No. 2014-109747

When molding an unsaturated polyester resin composition to obtain a light reflector, if general transfer molding is adopted as a molding method for the thermosetting resin composition, it can be expected that the light reflector will be mass-produced at low cost. .. In order to have good moldability during transfer molding, the unsaturated polyester resin composition is required to have higher fluidity than, for example, when an injection molding method is adopted. Further, the light reflector is required to have high heat-resistant discoloration property in order to maintain high light reflectivity for a long period of time.

However, an unsaturated polyester resin composition capable of obtaining a light reflector having good fluidity suitable for transfer molding and having high heat-resistant discoloration has not been obtained conventionally. Although Patent Document 1 describes not only an injection molding method but also a transfer molding method as a molding method, the molding method adopted in the examples in Patent Document 1 is only an injection molding method. Patent Document 1 does not disclose that an unsaturated polyester resin is used to obtain a light reflector having high heat-resistant discoloration by a transfer molding method.

The present invention has been made in view of the above points, and is a molding material for a light reflector, which has excellent fluidity and can obtain a light reflector having high heat-resistant discoloration by molding. It is an object of the present invention to provide a light reflector manufactured from a molding material for a light reflector, and a light emitting device including the light reflector.

The molding material for a light reflector according to the present invention contains an unsaturated polyester and a filler, and the unsaturated polyester comprises a fumaric acid residue, a 1,4-butanediol residue, and a trimethylolpropane residue. It is characterized by containing a compound.

The light reflector according to the present invention is characterized by containing a cured product of the molding material for the light reflector.

The light emitting device according to the present invention is characterized by including the light reflector and a light emitting element.

According to the present invention, it is possible to obtain a molding material for a light reflector, which has excellent fluidity and can obtain a light reflector having high heat-resistant discoloration by molding.

According to the present invention, a light reflector having high heat-resistant discoloration can be obtained.

According to the present invention, it is possible to obtain a light emitting device including a light reflector having high heat-resistant discoloration.

It is sectional drawing which shows the light emitting device provided with the light reflector in one Embodiment of this invention. It is a top view which shows the light emitting device shown in FIG. It is a top view which shows the molded body obtained when the light reflector is manufactured by the MAP method.

The molding material for a light reflector (hereinafter referred to as a molding material) according to the present embodiment is used for manufacturing the light reflector 1. This molding material contains unsaturated polyester and filler. The molding material may further contain a cross-linking agent.

In the present embodiment, the filler is a component composed of at least one of a white pigment, an inorganic filler and a fibrous filler. The filler preferably contains at least a white pigment. The white pigment in the present embodiment is a pigment that is white and has a refractive index of 1.5 or more. The refractive index of the resin is usually around 1.5, and it is preferable that the difference between the refractive index of the white pigment and the refractive index of the resin is large.

In this embodiment, the unsaturated polyester contains a compound containing a fumaric acid residue, a 1,4-butanediol residue and a trimethylolpropane residue (hereinafter referred to as the first unsaturated polyester).

The first unsaturated polyester is synthesized by dehydrating and condensing a raw material monomer containing, for example, fumaric acid, 1,4-butanediol and trimethylolpropane.

Since the first unsaturated polyester has the above constitution, the viscosity of the first unsaturated polyester at the time of melting is reduced. Therefore, the fluidity of the molding material containing the first unsaturated polyester during molding becomes high, and the moldability when the molding material is molded by the transfer molding method is improved. Further, the first unsaturated polyester may have a melting point suitable for transfer molding and high crystallinity by providing the above structure. Further, since the first unsaturated polyester has high reactivity, unreacted components are unlikely to remain in the molded product obtained by thermosetting the molding material. Therefore, the heat-resistant discoloration property of the light reflector 1 produced from the molding material is improved. As a result, the high light reflectivity of the light reflector 1 can be easily maintained for a long period of time.

The first unsaturated polyester is preferably crystalline. That is, the first unsaturated polyester is preferably a crystalline unsaturated polyester. When the first unsaturated polyester has crystallinity, the storage stability of the molding material is enhanced. That is, the molding material has high stability at a temperature below the melting point of the first unsaturated polyester. Further, the fluidity of the molding material is improved at the time of molding, so that good moldability can be obtained. Further, when the first unsaturated polyester has crystallinity, the light reflectance of the light reflector 1 can be increased, and the sustainability of the high light reflectance can also be enhanced.

In the present embodiment, the crystalline unsaturated polyester is an unsaturated polyester having crystallization, which has a melting point lower than room temperature, is a solid at room temperature, and is a liquid having a low viscosity above the melting point. .. The fact that the first unsaturated polyester has crystallinity means that, for example, when the first unsaturated polyester is heated and melted and then cooled to room temperature at a rate of -10 ° C./min, it becomes cloudy. Confirmed by occurring. Further, it was observed using a polarizing microscope that this crystallinity causes polarization characteristics when the first unsaturated polyester is heated and melted and then cooled to room temperature at a rate of -10 ° C./min. It is also confirmed by being done. Such confirmation of crystallinity is performed using, for example, a cooling / heating stage for a microscope manufactured by Rinkamu.

The glass transition temperature of the first unsaturated polyester is preferably in the range of 30 to 50 ° C. The melting point of the first unsaturated polyester is preferably in the range of 70 to 100 ° C.

When the glass transition temperature of the first unsaturated polyester is 30 ° C. or higher, the storage stability of the molding material is particularly high. That is, for example, when the molding material is crushed into granules and then stored, the particles of the molding material are prevented from being fused to each other at a high temperature such as in summer. Further, it is not preferable that the glass transition temperature is higher than 50 ° C. because the melting point of the first unsaturated polyester may become too high accordingly. The glass transition temperature of the first unsaturated polyester can be easily adjusted by adjusting the composition ratio and the molecular weight of the constituent components.

When the melting point of the first unsaturated polyester is 100 ° C. or lower, it becomes easy to melt the first unsaturated polyester without advancing the curing reaction during heat kneading for preparing a molding material. Therefore, a molding material containing no cured product can be easily prepared. Further, when the melting point of the first unsaturated polyester is 70 ° C. or higher, the decrease in the light reflectance of the light reflector 1 is suppressed. The reason is presumed to be as follows. When the molding material is crushed by the crushing device, the first unsaturated polyester is melted by the heat generated by the crushing device, frictional heat, etc., that is, the molding material is partially melted. When the partially melted molding material collides with a metal part such as a rotary blade in a crusher, the molding material tends to rub against each other in contact with the metal part. Then, the hard components such as the white pigment and the inorganic filler in the molding material rub against each other, and the metal parts generate metal powder, which is easily mixed in the molding material. It is considered that this metal powder causes a decrease in the light reflectance of the light reflector 1. However, when the melting point of the first unsaturated polyester is 70 ° C. or higher, the first unsaturated polyester is less likely to melt when the molding material is pulverized by a pulverizer. Then, when the molding material collides with a metal part such as a rotary blade, the molding material is likely to be quickly crushed, and therefore, the molding material and the metal part are less likely to rub against each other. Therefore, the metal powder is less likely to be mixed into the molding material, and thus the decrease in the light reflectance of the light reflector 1 is suppressed.

Further, the first unsaturated polyester having a melting point in the range of 70 to 100 ° C. can impart particularly excellent fluidity to the molding material when the molding material is molded, so that the molding material is transferred. Moldability is improved even when molded by a molding method.

The melting point of the first unsaturated polyester is a temperature at which a peak of heat of fusion appears when differential scanning calorimetry (DSC) is performed while raising the temperature of the first unsaturated polyester.

The iodine value of the first unsaturated polyester is preferably in the range of 70-120. When the iodine value is 70 or more, the glass transition temperature of the light reflector 1 becomes particularly high, and when the iodine value is 120 or less, the reactivity of the light reflector 1 decreases and the intensity of the light reflector 1 becomes particularly high. .. It is more preferable that the iodine value is in the range of 80 to 110.

The iodine value of the first unsaturated polyester can be easily adjusted, for example, by adjusting the proportion of fumaric acid residues in the first unsaturated polyester.

The ICI viscosity (high shear viscosity) of the first unsaturated polyester at 150 ° C. is preferably in the range of 0.1 to 5 Pa · s, preferably in the range of 0.5 to 3 Pa · s. Especially preferable. In this case, an appropriate fluidity is imparted to the molding material at the time of molding, the moldability is particularly good, and the generation of burrs is effectively suppressed. The ICI viscosity of the first unsaturated polyester can be easily adjusted by appropriately adjusting the composition of the first unsaturated polyester.

The structure of the first unsaturated polyester will be described in more detail.

The first unsaturated polyester comprises a polybasic acid residue and a polyol residue.

The molar ratio of the polybasic acid residue to the polyol residue in the first unsaturated polyester is, for example, in the range of 1: 1.1 to 1: 1.3. That is, the first unsaturated polyester is synthesized by, for example, a dehydration condensation reaction of polybasic acids and polyols at a molar ratio of 1: 1.1 to 1: 1.3.

In this embodiment, the polybasic acid residue contains a fumaric acid residue. Therefore, the first unsaturated polyester has good reactivity. Therefore, the residual unreacted components when the molding material is thermoset are reduced, and the heat-resistant discoloration property of the light reflector 1 is particularly improved.

The percentage of the fumaric acid residue to the total polybasic acid residue in the first unsaturated polyester is preferably 50 mol% or more. In this case, the heat-resistant discoloration property of the light reflector 1 is particularly high because the proportion of fumaric acid residues that do not contain an aromatic ring in the first unsaturated polyester is high. It is more preferable that the percentage of fumaric acid residue is in the range of 50 to 70 mol%, and further preferably in the range of 55 to 65 mol%.

The polybasic acid residue in the first unsaturated polyester may contain only a fumaric acid residue, or may contain a fumaric acid residue and other groups.

In particular, the polybasic acid residue preferably contains a fumaric acid residue and a terephthalic acid residue. In this case, the toughness of the light reflector 1 is improved. Further, since the first unsaturated polyester has an aromatic ring, particularly when the cross-linking agent also has an aromatic ring, the compatibility between the first unsaturated polyester and the cross-linking agent is improved, so that the light reflector 1 can be used. The characteristics are improved. The percentage of the terephthalic acid residue to the total polybasic acid residue in the first unsaturated polyester is preferably 50 mol% or less. It is more preferable that the percentage of terephthalic acid is in the range of 25 to 50 mol%, and further preferably in the range of 30 to 40.

The polybasic acid residue is selected from the group consisting of maleic acid residue, citraconic acid residue, mesaconic acid residue, itaconic acid residue, tetrahydrophthalic acid residue, methyltetrahydrophthalic acid residue, and glutaconic acid residue. It may further contain one or more unsaturated polybasic acid residues.

The polybasic acid residues are phthalic acid residue, 1,4-cyclohexanedicarboxylic acid residue, isophthalic acid residue, succinic acid residue, adipic acid residue, sebatic acid residue, azelaic acid residue, and endo. It may contain one or more saturated polybasic acid residues selected from the group consisting of methylenetetrahydrophthalic acid residues, hetic acid residues, and tetrabromphthalic acid residues. In this case, the heat-resistant discoloration property of the light reflector 1 is particularly improved.

The polyol residue contains a 1,4-butanediol residue and a trimethylolpropane residue as described above. By including the trimethylolpropane residue as well as the 1,4-butanediol residue as the polyol residue in this way, the crystallinity of the first unsaturated polyester is improved and the viscosity is reduced, whereby the molding material is formed. Improves moldability.

The total percentage of 1,4-butanediol residues and trimethylolpropane residues to the total polyol residues in the first unsaturated polyester is preferably 80 mol% or more. This percentage may be 100 mol%. When this percentage is 80 mol% or more, crystallization of the cured product is promoted when the molding material is cured, and therefore the dimensional stability of the light reflector 1 is improved.

The percentage of 1,4-butanediol residues to total polyol residues in the first unsaturated polyester is preferably in the range of 70-96 mol%. When this percentage is 70 mol% or more, the viscosity of the molding material at the time of molding is particularly reduced. Further, when this percentage is 96 mol% or less, good moldability at the time of molding can be ensured. Particularly preferred is the percentage of 1,4-butanediol residues to total polyol residues in the range of 75-95 mol%.

The percentage of trimethylolpropane residues to all polyol residues in the first unsaturated polyester is preferably in the range of 10-25 mol%. In this case, the crystallinity of the first unsaturated polyester can be appropriately suppressed. Further, when the percentage ratio of the trimethylolpropane residue is in the above range, the compatibility between the first unsaturated polyester in the molding material and the cross-linking agent or the like is improved, and thus the characteristics such as the uniformity of the light reflector 1 are improved. Is improved. It is considered that this is because the crystallinity of the first unsaturated polyester is appropriately lowered by the trimethylolpropane residue as described above. It is particularly preferable that the percentage of the trimethylolpropane residue to the total polyol residue is in the range of 15 to 20 mol%.

The polyol residue in the first unsaturated polyester may comprise a 1,2-propanediol residue. In this case, it can be expected that the fluidity of the molding material is improved by lowering the viscosity at the time of molding. The percentage of 1,2-propanediol residues to all polyol residues in the first unsaturated polyester is preferably in the range of 0-30 mol%. In this case, the resin strength of the light reflector 1 is improved. More preferably, the percentage of 1,2-propanediol residues is in the range of 1-25 mol%.

The polyol residue may further contain a group other than the 1,4-butanediol residue, the 1,2-propanediol residue, and the trimethylolpropane residue. For example, the polyol residues are ethylene glycol residue, 1,3-propanediol residue, 1,4-butanediol residue, 1,3-butanediol residue, 1,5-pentanediol residue, and propylene glycol residue. Group, diethylene glycol residue, triethylene glycol residue, dipropylene glycol residue, hydride bisphenol A residue, bisphenol A propylene oxide compound residue, dibromneeopentyl glycol residue, 1,6-hexanediol residue, It can contain at least one group selected from the group consisting of neopentyl glycol residues and cyclohexane 1,4-dimethanol residues.

A type in which the polyol residue is selected from the group consisting of ethylene glycol residue, 1,3-propanediol residue, 1,4-butanediol residue, 1,5-pentanediol residue and cyclohexanedimethanol residue. It is also preferable to contain the above groups. In this case, the heat-resistant discoloration property of the light reflector 1 is particularly improved.

The acid value of the first unsaturated polyester is preferably in the range of 15 to 35 mg-KOH / g, more preferably in the range of 20 to 30 mg-KOH / g.

The first unsaturated polyester is synthesized, for example, by dehydrating and condensing a raw material monomer containing polybasic acids and polyols. In this case, the first unsaturated polyester has a polybasic acid residue derived from polybasic acids and a polyol residue derived from polyols. In this raw material monomer, polybasic acids contain fumaric acid and terephthalic acid, and polyols contain 1,4-butanediol, 1,2-propanediol, and trimethylolpropane.

Further, in the present embodiment, the reactivity of the first unsaturated polyester is low at room temperature, and therefore, the storage stability of the molding material containing the first unsaturated polyester is high.

Further, in the present embodiment, since the molding material contains the first unsaturated polyester, high adhesion between the cured product of the molding material and the metal can be obtained. Therefore, when the metal lead 2 is attached to the light reflector 1 made of the molding material (see FIG. 1), high adhesion between the light reflector 1 and the lead 2 can be obtained.

It is particularly preferable that the unsaturated polyester in the molding material contains only the first unsaturated polyester. Further, the unsaturated polyester is a compound containing the first unsaturated polyester and further lacking one or more groups among the fumaric acid residue, the 1,4-butanediol residue, and the trimethylolpropane residue (the first). Second unsaturated polyester) may also be contained. However, the percentage of the first unsaturated polyester to the whole unsaturated polyester is preferably 40% by mass or more, and more preferably 95% by mass or more.

The weight average molecular weight of the first unsaturated polyester is preferably in the range of 6000 to 10000. In this embodiment, it is possible to achieve the glass transition temperature, iodine value and ICI viscosity of the first unsaturated polyester at 150 ° C. within this range. The weight average molecular weight is measured by GPC (gel permeation chromatography).

The cross-linking agent is a component that builds a cross-linked structure between the chains of the unsaturated polyester by reacting with the unsaturated polyester.

The cross-linking agent is, for example, a vinyl-based polymerizable monomer such as styrene, vinyl toluene, divinylbenzene, α-methylstyrene, methyl methacrylate, vinyl acetate; diallyl phthalate, isodialyl phthalate, triallyl cyanurate, diallyl tetrabrom phthalate, Methacrylate-based and acrylate-based polymerizable monomers such as phenoxyethyl acrylate, 2-hydroxyethyl acrylate, and 1,6-hexanediol diacrylate; and prepolymers formed by polymerizing one or more of these polymerizable monomers. It can contain one or more compounds selected from the group consisting of.

In particular, the cross-linking agent preferably contains a compound having a boiling point of 150 ° C. or higher. In this case, volatilization of the cross-linking agent from the molding material is suppressed. Therefore, the generation of odor from the molding material is suppressed, and the working environment is improved. In addition, the stability of the composition of the molding material is increased. In particular, the cross-linking agent may contain one or more compounds selected from the group consisting of diallyl phthalate, isodialyl phthalate, diethylene glycol diacrylate, and polymers of these compounds as compounds having a boiling point of 150 ° C. or higher. preferable. The polymer is a polymer of at least one compound selected from the group consisting of diallyl phthalate, isodialyl phthalate and diethylene glycol diacrylate. In this case, volatilization of the cross-linking agent from the molding material is suppressed. Therefore, the generation of odor from the molding material is suppressed, and the working environment is improved. In addition, the stability of the composition of the molding material is increased. Further, the difference between the melting point of the first unsaturated polyester and the softening point of the cross-linking agent becomes small, so that a molding material having high uniformity can be easily obtained by heat kneading. Further, the glass transition point of the light reflector 1 becomes high, and the heat-resistant discoloration property of the light reflector 1 becomes high. The compound having a boiling point of 150 ° C. or higher includes a compound that does not boil under normal pressure and has a thermal decomposition temperature of 150 ° C. or higher.

It is also preferable that the cross-linking agent contains at least one compound of diallyl phthalate monomer and triallyl cyanurate. In this case, not only the effect of having a high boiling point can be obtained, but also mold contamination is suppressed when molding is performed by a mold molding method such as a transfer molding method.

The percentage of the cross-linking agent to the total amount of the unsaturated polyester and the cross-linking agent is particularly preferably in the range of 2 to 15% by mass. When the percentage is 2% by mass or more, the glass transition point of the light reflector 1 is particularly high, and when the percentage is 15% by mass or less, the heat-resistant discoloration property of the light reflector 1 is particularly high.

The molding material may contain a curing catalyst. In this case, the reaction between the unsaturated polyester and the cross-linking agent is promoted, and the cross-linked structure is efficiently constructed. Therefore, the moldability of the molding material and the shape stability of the light reflector 1 are improved. The curing catalyst can contain, for example, one or more compounds selected from the group consisting of a curing accelerator and a polymerization initiator.

The polymerization initiator can contain, for example, a heat-decomposable organic peroxide. Organic peroxides include, for example, 2,5-dimethyl-2,5- (t-butylperoxy) hexane, tert-butyl (3,5,5-trimethylhexanoyl) peroxide, and 1,4-bis [(t-). Butyl peroxide isopropyl] benzene, t-butyl peroxide-2-ethylhexyl monocarbonate, 1,1-di (t-hexyl peroxide) cyclohexane, 1,1-di (t-butyl peroxide) -3,3 , 5-trimethylcyclohexane, t-butylperoxyoctate, benzoyl peroxide, methyl ethyl ketone peroxide, acetylacetone peroxide, t-butylperoxybenzoate, and one or more compounds selected from the group consisting of dicumyl peroxide. Can be contained.

Commercially available organic peroxide products are provided by NOF Corporation, Kayaku Akzo Corporation, Yoshitomi Arkema Corporation, and others. The organic peroxide is appropriately selected in consideration of the fact that, for example, odor due to decomposition products is unlikely to be generated during molding, the formation of unsaturated bonds is suppressed during molding, and the deterioration of heat-resistant discoloration is suppressed. .. The organic peroxide and the inorganic filler may be master-batched. In this case, the organic peroxide can be satisfactorily dispersed in the molding material.

The polymerization initiator preferably contains an organic peroxide having a 10-hour half-life temperature of 100 ° C. or higher. Specifically, the polymerization initiator preferably contains dicumyl peroxide. When the polymerization initiator contains such an organic peroxide, the decrease in reflectance of the light reflector 1 with time is further suppressed.

The percentage of the organic peroxide to the total amount of the unsaturated polyester and the cross-linking agent in the molding material is preferably in the range of 1 to 3% by mass. When this percentage is 1% by mass or more, the curing reaction of the molding material can be effectively promoted. Further, when the percentage is 3% by mass or less, it is possible to suppress the molding time from being excessively shortened and to prevent defects such as blurring in the light reflector 1.

The molding material may contain a polymerization inhibitor. Polymerization inhibitors include, for example, hydroquinone, monomethyl ether hydroquinone, toluhydroquinone, di-t-4-methylphenol, monomethyl ether hydroquinone, phenothiazine, t-butylcatechol, parabenzoquinone, pyrogallol and other quinones, 2,6-di-. t-butyl-p-cresol, 2,2-methylene-bis- (4-methyl-6-t-butylphenol), 1,1,3-tris- (2-methyl-4-hydroxy-5-t-butyl) It can contain one or more compounds selected from the group consisting of phenolic compounds such as phenyl) butane.

The molding material may contain only the unsaturated polyester resin as the thermosetting resin, but may further contain other thermosetting resins such as epoxy resin. However, the percentage of the unsaturated polyester resin to the total thermosetting resin is preferably 50% by mass or more.

The filler preferably contains a white pigment. The white pigment imparts light reflectivity to the light reflector 1 formed from the molding material. White pigments consist of, for example, titanium oxide, barium titanate, strontium titanate, aluminum oxide, magnesium oxide, zinc oxide, zinc sulfide, barium sulfate, magnesium carbonate, barium carbonate and white lead (ie, basic lead carbonate). It can contain one or more selected materials.

In particular, the white pigment preferably contains one or more materials selected from the group consisting of titanium oxide, barium titanate, barium sulfate, zinc oxide, and zinc sulfide. When the white pigment contains zinc oxide, the thermal conductivity of the light reflector 1 is particularly high, which is preferable. It is also preferable that the white pigment contains aluminum oxide having high thermal conductivity.

When the white pigment contains titanium oxide, the titanium oxide can contain one or more materials selected from, for example, anatase-type titanium oxide, rutile-type titanium oxide, and blusite-type titanium oxide. In particular, since rutile-type titanium oxide is excellent in thermal stability, it is preferable that the rutile-type titanium oxide contains rutile-type titanium oxide.

The surface of the white pigment may be surface-treated with a fatty acid, a coupling agent or the like. In this case, aggregation of the white pigment, oil absorption, etc. are suppressed, and the filling property of the white pigment in the molding material is improved.

The average particle size of the white pigment is preferably 2.0 μm or less. The average particle size is preferably 0.01 μm or more. The average particle size is preferably in the range of 0.03 to 1.0 μm, preferably in the range of 0.1 to 0.7 μm, and in the range of 0.2 to 0.5 μm. It is also preferable. The average particle size of the white pigment is measured by a laser diffraction / scattering method.

The percentage of the white pigment in the molding material is preferably in the range of 15 to 40% by mass. In this case, the heat-resistant discoloration property of the light reflector 1 is particularly high, and the light reflectivity of the light reflector 1 is also particularly high.

The filler may further contain an inorganic filler other than the white pigment. In this case, the light reflectivity of the light reflector 1 is further enhanced, and the shape stability of the light reflector 1 is further enhanced. In addition, the inorganic filler can increase the thermal conductivity of the light reflector 1. As a result, discoloration, deterioration, and the like due to heat of the light reflector 1 are further suppressed.

The inorganic filler can contain, for example, one or more materials selected from the group consisting of silica, calcium carbonate, calcium hydroxide, aluminum hydroxide, aluminum nitride, alumina, silicon nitride, boron nitride and mica.

The inorganic filler may contain a white extender pigment. In the present embodiment, the white extender pigment is a pigment that is white and has a refractive index of less than 1.5. When the molding material contains a white extender pigment, the light reflectivity of the light reflector 1 becomes particularly high. The white extender pigment can contain at least one material selected from the group consisting of, for example, calcium carbonate, barium sulfate and aluminum hydroxide.

The inorganic filler preferably contains silica in particular. In this case, the light reflectivity of the light reflector 1 is further enhanced, and the shape stability of the light reflector 1 is further enhanced. Silica can contain, for example, one or more materials selected from molten silica powder, spherical silica powder, crushed silica powder, and crystalline silica powder. In particular, it is preferable that silica contains molten silica.

It is also preferable that the inorganic filler contains a thermally conductive inorganic filler. In this case, the thermal conductivity of the light reflector 1 becomes particularly high, and therefore discoloration, deterioration, and the like due to heat of the light reflector 1 are further suppressed. The thermally conductive inorganic filler can contain one or more materials selected from the group consisting of, for example, crystalline silica, alumina, silicon nitride, boron nitride, aluminum nitride and the like.

The thermally conductive inorganic filler preferably contains a metal-containing filler, and particularly preferably contains an aluminum-containing filler. The aluminum-containing filler can contain, for example, aluminum hydroxide. Since aluminum hydroxide has a Mohs hardness of 3, it has an advantage that it is suppressed from being colored by rubbing with a kneader during kneading.

The inorganic filler may be surface-treated with a fatty acid, a coupling agent or the like. In this case, aggregation of the inorganic filler, oil absorption, and the like are suppressed, the filling property of the inorganic filler in the molding material is improved, and the moisture resistance reliability of the light reflector 1 is increased.

The percentage of hollow particles to the molding material is preferably in the range of 5 to 15% by mass. When the percentage of the hollow particles is 5% by mass or more, the ultraviolet resistance of the light reflector 1 is particularly improved. Further, when the percentage of the hollow particles is 15% by mass or less, it is possible to suppress an increase in the viscosity of the molding material during molding. It is more preferable that the percentage of the hollow particles is in the range of 5 to 10% by mass. When the percentage of the hollow particles is 10% by mass or less, an increase in the viscosity of the molding material can be particularly suppressed during molding.

The hollow particles are preferably surface-treated with one or more materials selected from the group consisting of calcium carbonate, zinc oxide and talc. That is, the hollow particles are preferably coated with one or more materials selected from the group consisting of calcium carbonate, zinc oxide and talc. In this case, the whiteness of the light reflector 1 is improved and the ultraviolet resistance of the light reflector 1 is also improved. One of the possible reasons is that the surface treatment of the hollow particles improves the dispersibility of the hollow particles in the molding material and the light reflector 1.

Preferred specific examples of the hollow particles include product number S60-HS (hollow glass beads) manufactured by Sumitomo 3M Ltd.

The average particle size of the inorganic filler is preferably 100 μm or less. In this case, the moldability of the molding material is particularly good, and the heat-resistant discoloration and moisture resistance of the light reflector 1 are particularly high. The average particle size is preferably 0.1 μm or more. In this case, the handleability of the molding material is improved. The average particle size of the inorganic filler is more preferably 80 μm or less, and even more preferably 50 μm or less. Further, the average particle size of the inorganic filler is more preferably 0.3 μm or more. Further, when the average particle size of the inorganic filler is in the range of 8 to 20 μm, the injection moldability of the molding material becomes particularly good. The average particle size of the inorganic filler is measured by a laser diffraction / scattering method.

The percentage of the inorganic filler to the total thermosetting resin in the molding material is preferably 40% by mass or more. In this case, the shape stability of the light reflector 1 is particularly high. The percentage of this inorganic filler is preferably 300% by mass or less. In this case, the moldability of the molding material is particularly high. It is particularly preferable that the percentage of the inorganic filler is in the range of 50 to 250% by mass.

The percentage of the white pigment to the entire filler is preferably 30% by mass or more. In this case, the light reflectivity of the light reflector 1 is particularly high. This percentage is preferably 95% by mass or less. This percentage is more preferably in the range of 35 to 90% by mass, and even more preferably in the range of 40 to 85% by mass.

The percentage of the filler to the total thermosetting resin in the molding material is preferably 500% by mass or less. In this case, the fluidity of the molding material becomes particularly high during molding. The percentage of the filler is preferably 100% by mass or more. In this case, the light reflectivity of the light reflector 1 is particularly high. The percentage of the filler is more preferably in the range of 100 to 400% by mass, and even more preferably in the range of 200 to 300% by mass.

The filler may or may not contain a fibrous filler.

The fibrous filler means a filler in which the value (L / D) of the ratio of the average fiber length (L) to the average fiber diameter (D) is in the range of 10 to 20. The average fiber length and the average fiber diameter of the fibrous filler are arithmetic mean values of the fiber length and the fiber diameter obtained by image-processing the microscopic image of the fibrous filler, respectively.

When the filler does not contain a fibrous filler, the fluidity of the molding material becomes very high during molding. In this case, even if the molding material is molded by the mold array package (MAP) method, excellent moldability can be obtained. The mold array package method is a method of obtaining a plurality of products by first collectively molding one molded body and cutting the molded body into a predetermined size to obtain a plurality of products.

On the other hand, when the filler contains the fibrous filler, the curing shrinkage of the molding material is suppressed during molding, the strength of the light reflector 1 is increased, and the dimensional stability of the light reflector 1 is further enhanced. Further, when the light reflector 1 integrated with the lead frame is manufactured by insert molding or the like, the warp of the light reflector 1 due to the molding shrinkage of the runner portion is suppressed.

The percentage of the fibrous filler to the total thermosetting resin in the molding material is preferably in the range of 10 to 200% by mass. In this case, the curing shrinkage of the molding material is particularly suppressed during molding, and the strength of the light reflector 1 is particularly high. The percentage of the fibrous filler is more preferably in the range of 20 to 100% by mass, and even more preferably in the range of 30 to 80% by mass.

Further, even when the filler contains the fibrous filler, if the amount of the filler in the molding material and the amount of the fibrous filler are appropriately set, the fluidity of the molding material becomes very high at the time of molding. Even if the molding material is molded by the MAP method, excellent moldability can be obtained. In this case, the percentage of the filler is preferably 50 to 70% by volume with respect to the entire molding material, and the percentage of the fibrous filler is preferably in the range of 5 to 20% by volume with respect to the entire molding material.

The fibrous filler can contain a fibrous filler used for FRP (fiber reinforced plastics) such as BMC (bulk molding compound) and SMC (sheet molding compound). ..

The average fiber diameter of the fibrous filler is preferably in the range of 6 to 12 μm, and more preferably in the range of 6 to 8 μm. In this case, the intensity of the light reflector 1 is particularly high. The average fiber length of the fibrous filler is preferably in the range of 100 to 300 μm, and more preferably in the range of 150 to 250 μm. In this case, the intensity of the light reflector 1 is particularly improved, and the light reflectance thereof is also particularly improved. The average fiber diameter and average fiber length of the fibrous filler are arithmetic average values of the fiber diameter and fiber length obtained by image-processing the electron micrographs of the fibers in the fibrous filler, respectively.

The fibrous filler is one or more materials selected from, for example, glass fiber, vinylon fiber, aramid fiber, polyester fiber, wallastnite, potassium titanate whiskers, whiskers of carbonates such as calcium carbonate, and hydrotalcite. Can be contained. In particular, the fibrous filler preferably contains glass fibers.

The glass fibers include, for example, silicate glass, E glass (non-alkali glass for electricity), C glass (alkali-containing glass for chemicals), A glass (acid resistant glass), and S glass (high-strength glass) made from silicate glass. ) And the like, which can contain one or more materials selected from the group consisting of glass fibers. The glass fiber may be a long fiber (roving) or a short fiber (chopped strand). The glass fiber may be surface-treated. In particular, the glass fibers have a length of 3 to 6 mm after the E glass fibers having a fiber diameter of 10 to 15 μm are converged with a converging agent such as vinyl acetate and then surface-treated with a silane coupling agent. It preferably contains chopped strands that are cut into pieces.

In particular, the average fiber diameter of the glass fiber is preferably in the range of 6 to 12 μm, and more preferably in the range of 6 to 8 μm. In this case, the intensity of the light reflector 1 is particularly high.

The average fiber length of the glass fiber is preferably in the range of 100 to 300 μm, and more preferably in the range of 150 to 250 μm. In this case, the intensity of the light reflector 1 is particularly improved, and the light reflectance thereof is also particularly improved. If the average fiber length is 100 μm or less, the glass fiber and the metal may rub against each other during kneading or injection molding, and the light reflectance of the light reflector 1 may decrease. The average fiber diameter and the average fiber length of the fibers are arithmetic mean values of the fiber diameter and the fiber length obtained by image processing the electron micrograph of the fiber, respectively.

Even if the average fiber length of the glass fiber before being blended into the molding material is not within the range of 100 to 300 μm, the average fiber length of the glass fiber in the molding material and the light reflector 1 is within the range of 100 to 300 μm. All you need is. For example, even if a glass fiber having a fiber length of about 3 mm is used, the average fiber length of the glass fiber in the molding material is within the range of 100 to 300 μm as a result of stress being applied to the glass fiber by kneading in the manufacturing process of the molding material. May become.

More specific examples of glass fibers are chopped strands with a diameter of 13 μm and a length of 3 to 5 mm, chopped strands with a diameter of 6 μm and a length of 3 to 5 mm, and an average fiber length of 250 with a diameter of 6 to 13 μm. Examples include milled fibers having a diameter of ~ 600 μm.

It is also preferable that the maximum fiber length of the glass fiber is 300 μm or less. In this case, when the molding material is molded by a mold molding method such as a transfer molding method, the molding material is less likely to be clogged with a gate or the like, so that unfilled defects are further suppressed. In particular, when a small light reflector 1 is manufactured to reflect the light of a light emitting element 3 such as a light emitting diode, the gate diameter becomes small, but even in such a case, clogging of the molding material at the gate or the like is suppressed. NS.

It is also preferable that the cross section of the glass fiber has a different shape. The irregular shape means a shape other than a circle, for example, a shape having an aspect ratio of more than 1 such as an eyebrows or an oval. The aspect ratio of the cross section is preferably 1.5 or more. Examples of such glass fibers include chopped strands having a modified cross section manufactured by Nitto Boseki Co., Ltd. When a glass fiber having such a deformed cross section is used, the strength of the light reflector 1 is improved. Further, by suppressing the warp of the light reflector 1, the flatness of the light reflector 1 is increased, and therefore the light reflectance is further improved.

It is also preferable that the fibrous filler is treated with an aliphatic urethane-based converging agent. In this case, the fibrous filler is bundled with an aliphatic urethane-based converging agent, and the adhesion between the resin in the molding material and the light reflector 1 and the fibrous filler is improved. As a result, the dispersibility of the fibrous filler in the molding material and in the light reflector 1 is improved. Therefore, the fibrous filler can effectively improve the mechanical strength of the light reflector 1, and the fibrous filler is less likely to inhibit the light reflectivity of the light reflector 1, resulting in light. The high intensity and high light reflectivity of the reflector 1 are ensured. Further, since the aliphatic urethane-based converging agent has few sites that cause yellowing such as unsaturated groups, it is difficult to yellow, so that the light reflectivity of the light reflector 1 is less likely to decrease with time.

It is preferable that the fibrous filler is first treated with an aminosilane coupling agent and then treated with an aliphatic urethane-based converging agent. In this case, the adhesion of the aliphatic urethane-based converging agent to the fibrous filler is increased.

Aminosilane coupling agents include, for example, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -N'-β- (aminoethyl). It can contain one or more compounds selected from the group consisting of −γ-aminopropyltriethoxysilane and γ-anilinopropyltrimethoxysilane. The percentage of the aminosilane coupling agent is preferably 0.3% by mass or less, more preferably 0.2% by mass or less, based on the fibrous filler.

The aliphatic urethane-based converging agent can include an isocyanate residue and a polyol residue. The aliphatic urethane-based converging agent is obtained by reacting an isocyanate compound that induces an isocyanate residue, a polyol compound that induces a polyol residue, and an additive selected from a chain extender and a cross-linking agent, if necessary.

In particular, the isocyanate residues in the aliphatic urethane-based converging agent are isophorone diisocyanate residue, hexamethylene diisocyanate residue, isophorone diisocyanate residue, methylenebis (4,5-cyclohexylene) diisocyanate residue, and 1,3-bis ( Isocyanatomethyl) contains one or more groups selected from the group consisting of cyclohexane residues, norbornandiisocyanate residues and metaxylylene diisocyanate residues, and the polyol residue in the aliphatic urethane-based converging agent is polycaprolactone. It preferably contains one or more groups selected from the group consisting of polyols, polybutadiene polyols and polycarbonate polyols. In this case, the yellowing of the aliphatic urethane-based converging agent is particularly suppressed, so that the yellowing of the light reflector 1 due to light and heat and the decrease in reflectance are particularly suppressed.

The aliphatic urethane-based converging agent comprises at least one of an aliphatic diisocyanate residue and an alicyclic diisocyanate residue, and a polyester polyol residue, and the polyester polyol residue is an aliphatic polybasic acid residue. It is also preferable to include at least one of the alicyclic polybasic acid residues and an aliphatic polyhydric alcohol residue. In this case, the yellowing of the aliphatic urethane-based converging agent is particularly suppressed, so that the yellowing of the light reflector 1 due to light and heat and the decrease in reflectance are particularly suppressed.

The aliphatic urethane-based converging agent comprises at least one group of an isophorone diisocyanate residue and a hexane-1,6-diisocyanate residue, and a polyester polyol residue, and the polyester polyol residue is a neopentyl glycol residue. It is also preferable to have at least one group of the propylene glycol residue and at least one group of the adipic acid residue and the phthalic acid residue. In this case, the yellowing of the aliphatic urethane-based converging agent is particularly suppressed, so that the yellowing of the light reflector 1 due to light and heat and the decrease in reflectance are particularly suppressed. In particular, the isocyanate residue in the aliphatic urethane-based converging agent consists of isophorone diisocyanate residue and hexane-1,6-diisocyanate residue, and the polyester polyol residue in this aliphatic urethane-based converging agent is neopentyl glycol residue. It preferably consists of a propylene glycol residue, an adipic acid residue and a phthalic acid residue.

The percentage of the aliphatic urethane-based converging agent to the fibrous filler is not particularly limited, but is preferably in the range of 0.05 to 0.4% by mass, preferably in the range of 0.05 to 0.29% by mass. If it is, it is more preferable.

The percentage of the fibrous filler to the entire molding material is preferably in the range of 3 to 20% by mass, and more preferably in the range of 5 to 15% by mass. In these cases, the bending strength of the light reflector 1 is particularly improved. Further, in these cases, the material shrinkage rate can be reduced. That is, the occurrence of cracks in the light reflector 1 is suppressed in a temperature cycle test or the like. In particular, when the light reflector 1 is produced from the molding material by the MAP method, the percentage of the fibrous filler to the entire molding material is preferably in the range of 5 to 20% by volume.

The percentage of the filler to the entire molding material is preferably in the range of 20 to 90% by mass. In this range, excellent fluidity of the molding material is ensured during molding. In particular, when the light reflector 1 is produced from the molding material by the MAP method, the percentage of the filler with respect to the entire molding material is preferably in the range of 50 to 70% by volume. Further, when one light reflector 1 is manufactured per cavity by molding the molding material by the transfer molding method instead of the MAP method, the percentage of the filler to the entire molding material is 50 to 90% by mass. It is preferably in the range of 60 to 85% by mass, and particularly preferably in the range of 60 to 85% by mass.

The molding material preferably contains an antioxidant. In this case, the discoloration of the light reflector 1 is further suppressed, and the deterioration of the light reflectivity of the light reflector 1 with time is less likely to occur. The antioxidant can contain, for example, one or more compounds selected from the group consisting of phenolic antioxidants and phosphorus-based antioxidants. It is preferable that the antioxidant does not contain a compound that produces a chromophore.

The molding material preferably contains a phosphorus-based antioxidant. In this case, the yellowing of the light reflector 1 during processing and the yellowing over time are further suppressed, whereby the decrease in the light reflectance of the light reflector 1 is further suppressed. In particular, when the molding material contains triglycidyl isocyanurate, if a phosphorus-based antioxidant is also contained, the decrease in the light reflectance of the light reflector 1 is significantly suppressed.

Phosphoric antioxidants include, for example, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 3,9-bis (2,6-di-tert-butyl-4-methylphenoxy)-. Selected from the group consisting of 2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, bis (nonylphenyl) pentaerythritol-di-phosphite and distearyl pentaerythritol-di-phosphite. Can contain one or more compounds. The percentage of the phosphorus-based antioxidant in the molding material is preferably in the range of 0.1 to 0.5% by mass.

It is also preferable that the molding material contains a sulfur-based antioxidant. Specific examples of the sulfur-based antioxidant include ADEKA Corporation's product name ADEKA STAB AAA-412S. The percentage of the sulfur-based antioxidant in the molding material is preferably 0.5% by mass or less, and more preferably 0.01 to 0.5% by mass.

The molding material may contain a mold release agent. The release agent can contain, for example, one or more materials selected from the group consisting of commonly used fatty acid-based waxes, fatty acid metal salt-based waxes, and mineral-based waxes. In particular, the release agent preferably contains a fatty acid-based wax or a fatty acid metal salt-based wax having excellent heat-resistant discoloration.

The release agent preferably contains one or more materials selected from the group consisting of stearic acid, zinc stearate, aluminum stearate, and calcium stearate.

The amount of the release agent with respect to 100 parts by mass of the thermosetting resin is preferably in the range of 1 to 15 parts by mass. In this case, the good releasability of the light reflector 1 and the excellent appearance of the light reflector 1 are compatible with each other at the time of molding, and the light reflectivity of the light reflector 1 is particularly high.

In addition to the above components, the molding material may contain appropriate additives such as a colorant, a thickener, a flame retardant, and a flexibility-imparting agent.

The molding material may contain a thermoplastic resin. In this case, the shrinkage during molding is suppressed, so that the dimensional stability of the light reflector 1 is improved. The thermoplastic resin can contain one or more components selected from the group consisting of, for example, polystyrene, silicone elastoma, polyethylene, polypropylene, polyvinyl acetate, styrene butadiene rubber, acrylonitrile butadiene styrene rubber and polymethyl methacrylate. The thermoplastic resin is, for example, in the range of 0.5 to 20 parts by mass with respect to 100 parts by mass of the molding material.

The molding material may be solid. In this case, the storage stability and handleability of the molding material are improved. For example, the molding material may be granular, powdery or the like. In particular, the molding material is preferably solid at 30 ° C. or lower. In this case, the molding material can be easily processed into granules by pulverization processing, extrusion pellet processing, or the like. It is also preferable that the molding material has shape retention at 50 ° C. or lower. In this case, the handleability of the molding material and the workability when the molding material is used are particularly high.

The molding material may be prepared without solvent. In this case, a solid molding material can be easily obtained.

In the preparation of the molding material, for example, the above-mentioned raw materials are first mixed in a predetermined ratio and mixed with a mixer such as a mixer or a blender to obtain a mixture. This mixture is kneaded with a kneader, an extruder or the like capable of heating and pressurizing. As the kneader, for example, a pressure kneader, a heat roll, an extruder and the like are used. The heating temperature during this kneading is preferably in the range of 80 to 120 ° C. In this case, the first unsaturated polyester is melted without being cured, so that the uniformity of the molding material is improved. Subsequently, the bulk body of the mixture is pulverized and sized, or further granulated as necessary to obtain molding materials such as granules, powders, and pellets. Since the first unsaturated polyester is less likely to melt during pulverization in the present embodiment, a decrease in the light reflectance of the light reflector 1 due to metal scraping is suppressed.

As described above, the molding material according to the present embodiment contains the first unsaturated polyester, so that high fluidity can be obtained at the time of molding. By containing the first unsaturated polyester, the spiral flow length of the molding material according to the present embodiment at 170 ° C. is preferably 30 cm or more. By containing the first unsaturated polyester, it is also preferable that the torque of the curastometer at 170 ° C. of the molding material according to the present embodiment is 1.96 Nm (20 kgf cm) or more. In this case, the fluidity of the molding material is particularly excellent, the molding material is easily molded by the transfer molding method, and the generation of burrs on the light reflector 1 is suppressed.

When the filler does not contain a fibrous filler, the fluidity of the molding material becomes particularly high during molding. When the molding material contains the first unsaturated polyester and does not contain the fibrous filler, the spiral flow length of the molding material at 170 ° C. is 50 cm or more, and the torque of the curastometer at 170 ° C. is 1.96 Nm. It can be achieved that it is (20 kgf · cm) or more. In this case, the moldability is particularly good when the light reflector 1 is manufactured by the mold array package (MAP) method.

The light reflector 1 is obtained by molding and curing the molding material. As a molding method, an appropriate melt heating molding method such as an injection molding method, an injection compression molding method, or a transfer molding method can be applied. In particular, as described above, it is preferable to apply a transfer molding method that is low in cost and easy to mass-produce. The molding conditions in the transfer molding method are, for example, a mold temperature in the range of 150 to 195 ° C., preferably 170 to 180 ° C., a transfer pressure in the range of 5 to 20 MPa, and a curing time of 30 to 300 seconds, preferably 30. It is within the range of ~ 180 seconds. Post-cure treatment may be applied if necessary.

1 and 2 show an example of a light emitting device 6 including a light reflector 1. The light emitting device 6 includes a light reflector 1, a metal reed 2, and a light emitting element 3. In this example, the light reflector 1 and the lead 2 are combined by attaching the lead 2 to the light reflector 1. The structure of the light reflector 1 and the light emitting device 6 manufactured from the molding material according to the present embodiment is not limited to this example.

The lead 2 includes a first lead 21 and a second lead 22. The light reflector 1 includes a main body portion 12 that is superposed on the lead 2, and an intervening portion 11 that is interposed between the first lead 21 and the second lead 22. The main body 12 is formed with a recess 13 that opens on the upper surface thereof. Each of the first lead 21 and the second lead 22 is exposed in the recess 13 at the bottom surface of the recess 13. On the lower surface of the lead 2, an insulating member 5 straddling the first lead 21 and the second lead 22 is provided, and the member 5 is the first lead 21 and the second lead 22. Suppress a short circuit with.

The light emitting element 3 is, for example, a light emitting diode, but is not limited thereto. The light emitting element 3 is mounted on the first lead 21 in the recess 13. Further, in the recess 13, the light emitting element 3 and the first lead 21 are electrically connected by the first wire 41, and the light emitting element 3 and the second lead 22 are connected by the second wire 42. Has been done.

The inner peripheral surface 14 of the recess 13 of the light reflector 1 is inclined so that the inner diameter of the recess 13 becomes larger toward the opening side. Therefore, the light emitted from the light emitting element 3 is easily reflected by the inner peripheral surface 14 of the recess 13 in the light reflector 1, and as a result, the light extraction efficiency from the light emitting device 6 is increased.

In the light emitting device 6, if necessary, the inside of the recess 13 may be sealed with a transparent resin, or the opening of the recess 13 may be covered with a transparent cover.

The light reflector 1 to which such a metal lead 2 is attached is manufactured by, for example, an insert molding method. That is, for example, a lead frame including the lead 2 is arranged inside the transfer molding die, and in this state, the molding material is transferred in the transfer molding die, and the lead 2 is separated from the lead frame if necessary. , Light reflector 1 is obtained.

A method of manufacturing the light reflector 1 to which the metal reed 2 is attached by the MAP method will be described with reference to FIG. For example, first, a lead frame 20 including 2 of a plurality of leads is prepared. The lead frame 20 is arranged inside the transfer molding die, and in this state, the molding material is transferred in the transfer molding die. As a result, a molded body 10 to which the lead frame 20 is attached is obtained. By cutting the molded body 10 with a dicing saw or the like, a plurality of light reflectors 1 can be obtained.

[Preparation of unsaturated polyester]
The raw material monomers having the compositions shown in Table 1 below were placed in a container, and the temperature was raised while replacing the inside of the container with an inert gas, and the raw material monomers were reacted while purging the condensed water. The reaction was terminated when it was confirmed that the acid value of the product was in the range of 5-40 mg-KOH / g. As a result, a crystalline unsaturated polyester was obtained.

The iodine value, melting point, ICI viscosity at 150 ° C. and weight average molecular weight of each unsaturated polyester are also shown in Table 1. The melting point is a value measured by differential scanning calorimetry (DSC) of unsaturated polyester while raising the temperature at 10 ° C. per minute.

[Examples and Comparative Examples]
A resin component having the composition shown in the table below and a filler were prepared, and these were blended so that the ratio of the filler became the value shown in "the ratio of the filler in the molding material" in the table. The amounts of the raw materials shown in the "resin component composition" column and the "filler composition" column in the table are both indicated by parts by mass. These raw materials were uniformly mixed using a sigma blender and then kneaded with a hot roll heated to 100 ° C. to obtain a sheet-shaped kneaded product. This kneaded product was cooled, crushed, and sized. As a result, a granular molding material was obtained.

The results of measuring the spiral flow length at 170 ° C. and the torque of the curast meter at 170 ° C. of the molding material are shown in Tables 2 to 5 below. In measuring the spiral flow, the molding material was molded under the conditions of a molding temperature of 170 ° C. and a molding pressure of 6.9 MPa using a mold for measuring spiral flow according to the standard of EMMI-1-66. The flow distance (cm) was calculated. In measuring the torque of the curast meter, the molding material was heated at a temperature of 170 ° C., and the torque value 180 seconds after the start of heating was obtained.

The details of the raw materials shown in the table below other than the unsaturated polyester are as follows.

Crosslinking agent / diallyl phthalate monomer: manufactured by Daiso Corporation, product name Dapp monomer, molecular weight 246.3, viscosity 8.5 mPa · s at 30 ° C, iodine value 202, liquid at room temperature, boiling point 290 ° C.
Triallyl cyanurate: manufactured by Nihon Kasei Corporation, product name Tyke, molecular weight 249, viscosity 80-110 mPa / s (30 ° C), melting point 27 ° C, boiling point 162 ° C (2 mmHg).

Curing accelerator ・ 2,5-dimethyl-2,5- (t-butylperoxy) hexane.
・ Dikmyl peroxide: Made by NOF CORPORATION.

Release agent, zinc stearate: manufactured by Sakai Chemical Industry Co., Ltd., product name SZ-P.

Antioxidant-PEP-36: Phosphorus-based antioxidant, manufactured by ADEKA Corporation, product name ADEKA STAB PEP-36.
-AO-60: Hindered phenolic antioxidant, manufactured by ADEKA Corporation, product name ADEKA STAB AO-60.
-AO-412S: Sulfur-based antioxidant, manufactured by ADEKA Corporation, product name ADEKA STAB AAO-412S.

White pigment / titanium oxide: Rutile type titanium oxide, average particle size 0.4 μm, manufactured by Thai Oxide Japan Co., Ltd., product name Tioxide RTC-30.

Inorganic filler / silica: fused silica, average particle size 25 μm, manufactured by Denki Kagaku Kogyo Co., Ltd., product name FB-820.
-Hollow particles: Glass hollow particles, average particle size 30 μm, manufactured by Sumitomo 3M Ltd., trade name Glass Bubbles, product number S60-HS.

Fibrous filler / glass fiber: Glass fiber with average fiber length of 3 mm, average fiber diameter of 10.5 μm, moisture content of 0.02%, and strong heat loss of 0.28%, surface treatment with aminosilane coupling agent and aliphatic urethane A treated product obtained by sequentially performing surface treatment with a system converging agent. In the aliphatic urethane-based converging agent, the isocyanate residue is composed of 80 mol% or more of isophorone diisocyanate residue and 20 mol% or less of hexane-1,6-diisocyanate residue, and the polyester polyol residue is neopentyl glycol residue. It consists of propylene glycol residues, adipic acid residues and phthalic acid residues.

[evaluation]
(Light reflectance)
1. 1. An evaluation sample was prepared by transfer molding the initial molding material. The transfer molding conditions were a mold temperature of 170 ° C., a transfer pressure of 8 MPa, and a curing time of 90 seconds. The dimensions of the evaluation sample were 5 cm in diameter and 1 mm in thickness.

The light reflectance of this evaluation sample at a wavelength of 460 nm was measured using a spectrocolorimeter CM-3500d manufactured by Konica Minolta.

2. After the heat treatment, the evaluation sample was heat-treated at 150 ° C. for 1000 hours, and then the light reflectance of this sample at a wavelength of 460 nm was measured.

3. 3. After UV Irradiation / Heat Treatment The evaluation sample was heat-treated at 140 ° C. for 1000 hours while irradiating UV light using a HID lamp (high-pressure mercury lamp) as a light source. Subsequently, the light reflectance of this sample at a wavelength of 460 nm was measured.

4. After the high temperature and high humidity treatment, the evaluation sample was treated at 85 ° C. and 85% RH for 1000 hours, and then the light reflectance of this evaluation sample at a wavelength of 460 nm was measured.

(Odor during molding)
An evaluation sample was prepared under the same conditions as in the case of the above evaluation of light reflectance. The odor of the environment around the mold at the time of this molding was sensory evaluated. As a result, the case where a strong odor was felt was evaluated as "B", and the case where it was not felt was evaluated as "A".

(Storage stability)
The molding materials obtained in each Example and Comparative Example were analyzed by differential scanning calorimetry (DSC) immediately after preparation, and the amount of heat generated during heat generation was measured. Further, after storing this molding material at a temperature of 20 ° C. for one month, the calorific value of this molding material at the time of heat generation was measured. As a result, the case where the calorific value of the molding material after storage was 80% or more of the calorific value of the molding material immediately after preparation was evaluated as "A", and the case where it was less than 80% was evaluated as "B".

(Individual moldability)
A sample for evaluation of a light reflector was prepared by transferring a molding material using a transfer molding die having a cavity having dimensions of 3 mm × 3 mm × 1 mm. The transfer molding conditions were a mold temperature of 170 ° C., a transfer pressure of 8 MPa, and a curing time of 90 seconds.

2500 evaluation samples were prepared and observed to confirm the presence or absence of unfilled defects. The number of evaluation samples in which defects were found was counted, and the moldability was evaluated by this number.

(MAP method formability)
A mold for batch molding was prepared in which 196 cavities having dimensions of 3 mm × 3 mm × 1 mm were arranged in a matrix of 14 rows and 14 columns to form one cavity. The molding material was transfer-molded with the copper lead frame set in the batch molding die. The transfer molding conditions were a mold temperature of 170 ° C., a transfer pressure of 8 MPa, and a curing time of 90 seconds. By cutting the molded product thus obtained with a dicing saw, 196 light reflectors were cut out from one molded product.

In the evaluation, 1960 light reflectors were obtained as evaluation samples by molding 10 molded bodies. The evaluation sample was observed to confirm the presence or absence of unfilled defects. The number of evaluation samples in which defects were found was counted, and the moldability was evaluated by this number.

1 Light reflector 6 Light emitting device

Claims (10)

A light reflector containing a cured product of a molding material for a light reflector and a light emitting element are provided.
The molding material for a light reflector contains an unsaturated polyester and a filler, and contains
The unsaturated polyester contains a compound comprising a fumaric acid residue, a 1,4-butanediol residue, and a trimethylolpropane residue.
The compound further comprises a 1,2-propanediol residue.
A light emitting device in which the filler contains a white pigment. A light reflector containing a cured product of a molding material for a light reflector and a light emitting element are provided.
The molding material for a light reflector contains an unsaturated polyester and a filler, and contains
The unsaturated polyester contains a compound comprising a fumaric acid residue, a 1,4-butanediol residue, and a trimethylolpropane residue.
The iodine value of the compound is in the range of 70 to 120 and
A light emitting device in which the filler contains a white pigment. The light emitting device according to claim 2, wherein the compound further comprises a 1,2-propanediol residue. The light emitting device according to claim 1 or 3, wherein the percentage of the 1,2-propanediol residue to the total polyol residue in the compound is within the range of 10 mol% or less. The light emitting device according to any one of claims 1 to 4, wherein the molding material for a light reflector contains a cross-linking agent. The percentage of the 1,4-butanediol residue is in the range of 70 to 90 mol%, and the percentage of the trimethylolpropane residue is in the range of 10 to 25 mol% with respect to all the polyol residues in the compound. The light emitting device according to any one of claims 1 to 5. The light emitting device according to any one of claims 1 to 6, wherein the compound further contains a terephthalic acid residue. The light emitting device according to any one of claims 1 to 7, wherein the compound has crystallinity. The invention according to any one of claims 1 to 8, wherein the melting point of the compound is in the range of 70 to 100 ° C.
Light emitting device. From claim 1, the ICI viscosity of the compound at 150 ° C. is in the range of 0.1 to 5 Pa · s.
The light emitting device according to any one of 9.

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